Acting under orders of Prime Minister Li Keqiang, the 60-member strong investigation team will look at the conditions at the time of the Eastern Star's sinking, the structure and retrofitting of the ship, its fitness to sail and sailors' responsibility, and shipping safety supervision on the Yangtze River, among other aspects.
Bodies of 434 passengers, mostly elderly Chinese tourists, were recovered and search was on for eight of those listed missing in China's worst maritime disaster in almost 70 years. The missing persons are presumed dead.
A "multitude of first-hand evidence" has been collected by investigators looking into what caused the Yangtze river shipwreck, state-run Xinhua news agency quoted a government circular.
The investigation team was formed on June 2 to probe the shipwreck. Only 14 passengers survived including the Captain who along with chief engineer swam to the shore claiming that the vassal sank after hit by a freak tornado.
Also Read
Investigators have interviewed survivors, including the captain, shipping company managers, designers and builders of the Eastern Star, and witnesses from other ships.
IT experts are working to recover video footage and GPS data from devices recovered from the ship after it was hoisted from the water on Friday.
Data from satellites, radars and ground-level monitors is informing the investigation into the weather conditions at the time of the sinking.
The investigators have also been combing through the Eastern Star's certificates, design drawings and other engineering papers.
The Eastern Star was on an 11-day trip along the mighty Yangtze river with 456 people onboard when it capsized on June 1.